Hydraulic power tong

Abstract

A power tong apparatus provides a housing having a vertical U-shaped slot allowing a vertically supported length of drill pipe to be inserted into the slot coincident with a provided vertical axis of the slot. An upper and lower jaw assembly is provided in its respective jaw assembly carriage. The jaw assemblies are rotationally mounted within the respective jaw carriages and are powered by hydraulic cylinders. Four laterally extending chambers are provided which allow the hydraulic cylinders to be moved between left and right positions which combined with an inverting of the respective jaw assembly different rotational directions to each jaw assembly. Thus, the same jaw assemblies can be used to make up or disassemble pipe joints together. Openings are provided in the housing for the insertion of hydraulic lines into the housing for connection to the respective hydraulic cylinders. Cover plates provided externally on each laterally extending chamber allow for easy access to the hydraulic cylinder connections. Similarly, upper and lower cover plates allow for easy access to the respective upper and lower jaw assemblies. Teeth provided on each jaw assembly are removable for ease of replacement.

What is claimed as invention is: 
     
       1. A power tong apparatus comprising: a. a housing having a vertically arranged U-shaped bore allowing for the insertion of a section of vertically supported drill pipe there into, said bore having a vertical axis;   b. upper and lower cylindrical jaw assemblies carried respectively in the upper and lower portion of said housing, and mounted within cylindrical recesses provided respectively in the upper and lower portions of said housing, each of said jaw assemblies comprising: i. a jaw body having a U-shaped slot and being rotatably supported by said housing;   ii. a movable jaw portion movably mounted on said jaw body;   iii. toothed elements mounted on said jaw body and on said movable jaw, said toothed elements facing inwardly towards said vertical axis;     c. hydraulic cylinder means for powering said jaw assemblies in opposite rotational directions; and   d. clamp means associated with each of said upper and lower jaw assemblies for clamping a length of pipe inserted into said slots for rotation with said respective upper and lower jaw assemblies.   
     
     
       2. The apparatus of claim 1 wherein said housing provides four laterally extending chambers, a pair of upper opposed chambers and a pair of lower opposed chambers, and said hydraulic cylinder means is removably attachable to any one of said laterally extending chambers at one end portion thereof and its other end portion thereof to either said upper or said lower jaw assembly. 
     
     
       3. The apparatus of claim 2 wherein said hydraulic cylinder attaches respectively at one end portion to one of said laterally extending chambers and at its other end portion to the movably jaw portion of said jaw assembly. 
     
     
       4. The apparatus of claim 1 wherein said hydraulic cylinder means comprises at least one hydraulic cylinder. 
     
     
       5. The apparatus of claim 1 wherein said movable jaw portion can be powered by said hydraulic cylinder means to a first gripping position against a length of drill pipe and thereafter rotated with said jaw body to impart a rotational spin to said drill pipe. 
     
     
       6. The apparatus of claim 1 wherein said movable jaw portion is pivotally mounted to said jaw body. 
     
     
       7. The apparatus of claim 1 wherein said toothed elements are removably attached to said movable jaw and to said body. 
     
     
       8. A power tong apparatus comprising: a. a housing having a vertical U-shaped slot allowing a vertically supported length of drill pipe to be inserted into said slot coincident with a provided vertical housing axis which also defines the axis of said U-shaped slot;   b. upper and lower jaw assembly carriages, each of said carriages being cylindrical recesses formed respectively in the upper and lower portions of said housing, said recesses being symmetrical about said housing vertical axis;   c. a first toothed cylindrical jaw assembly rotatably supported within said first jaw carriage;   d. a second toothed cylindrical jaw assembly rotatable within said second jaw carriage and movable in a different rotational direction with respect to said first jaw assembly; each of said jaw assemblies comprising: i. a jaw body;   ii. a movable jaw pivotally attached to said jaw body;   iii. removable jaw elements attached respectively to said jaw body and said movable jaw.     e. a pair of powered jaws carried respectively on said upper and lower jaw assemblies for clamping a section of vertically supported drill pipe;   f. a pair of hydraulically powered cylinders attached respectively at one end portion to said housing and at their opposite end portion respectively to said pair of jaw assemblies, each of said hydraulic cylinders being removably affixed to different positions on said housing, each of said different positions allowing said cylinders to rotate their respective jaw assemblies in opposite rotational directions.   
     
     
       9. The apparatus of claim 8 wherein each of said jaw assemblies can be inverted within its associated jaw assembly carriage. 
     
     
       10. The apparatus of claim 8 further comprising a pair of upper laterally extending chambers and a pair of lower laterally extending chambers, each of said chambers being generally opposite from one another but symmetric about said axis, each of said chambers further providing attachment means for attaching said hydraulic cylinder thereto at one end portion thereof. 
     
     
       11. A power tong apparatus comprising: a. a housing having a U-shaped vertical slot with a vertical axis normally occupied by a pair of pipe lengths to be assembled or disassembled;   b. a pair of cylindrical jaw assemblies movably mounted within cylindrical recesses provided respectively in the upper and lower portions of said housing;   c. a pair of oppositely oriented hydraulic cylinders being connected respectively to said pair of jaw assemblies and producing opposite rotational motion of each, each jaw assembly being powered during operation by one of said cylinders to a first pipe gripping position and thereafter to a second pipe rotating position.   
     
     
       12. The apparatus of claim 11 wherein said housing further comprises four laterally extending chambers, a pair of upper laterally extending chambers and a pair of lower laterally extending chambers, and each of said laterally extending chambers provides attachment means for attaching one end portion of said hydraulic cylinders thereto. 
     
     
       13. The apparatus of claim 11 wherein each of said pair of jaw assemblies comprises: a. a jaw body;   b. a movable jaw pivotally attached thereto; and   c. a movable jaw bracket being provided on said movable jaw with an end portion of said hydraulic cylinder being attached thereto during operation for imparting powered pivotal movement to said movable jaw.